Resources · Compliance
Pallet Industry Standards:
ISPM-15, GMA & More
Pallet compliance isn't optional — it's the difference between a smooth shipment and a costly border rejection. This guide covers the major standards to know, from international phytosanitary rules to domestic pallet specs. Requirements change, so always check current regulations for your shipment.
ISPM-15: The Export Pallet Standard
ISPM-15 (International Standards for Phytosanitary Measures No. 15) is a set of guidelines developed by the International Plant Protection Convention (IPPC) to prevent the international transport of insects and plant diseases through wood packaging materials. It applies to all solid wood packaging — pallets, crates, dunnage — used in international trade.
The standard requires that wood packaging be treated to eliminate pests before crossing international borders. Approved treatments include heat treatment (HT), dielectric heating (DH), and methyl bromide fumigation (MB). Methyl bromide is banned or restricted in many places because it depletes ozone, so in practice heat treatment is the most common choice for exporters.
Heat treatment requires raising the core temperature of the wood to a minimum of 56°C (133°F) for at least 30 continuous minutes. Heat-treated pallets can be requested through partner suppliers, and treated pallets carry the IPPC mark applied by the treatment provider.
When You Need ISPM-15
- Most export shipments on wood pallets
- Imports requiring compliant packaging
- Customers with international supply chains
- Buyers whose specifications call for HT pallets
Rejection Risk
Shipping on non-compliant pallets can result in your entire container being rejected at the port, quarantined, fumigated at your expense, or returned to origin. Storage fees, re-treatment, and shipping delays add up quickly. Using ISPM 15 compliant pallets from the start is usually far cheaper than dealing with a rejection.
Understanding the IPPC Stamp
Every ISPM-15 compliant pallet carries a stamp from the International Plant Protection Convention. Here's how to read it.
IPPC Symbol
The wheat-ear logo of the International Plant Protection Convention confirms the mark is legitimate.
Country & Region
A two-letter country code followed by a region or producer number. “US” indicates United States origin.
Treatment Code
“HT” = Heat Treated. “MB” = Methyl Bromide (restricted in most countries). “DH” = Dielectric Heating.
Debarked
“DB” indicates the wood has been debarked per ISPM-15 requirements. All treated pallets must also be debarked.
Heat Treatment vs. Methyl Bromide
While ISPM 15 allows more than one treatment method, the industry has largely moved to heat treatment. Here's why.
Heat Treatment (HT)
Recommended- +Widely accepted by countries that enforce ISPM 15
- +No chemical residues on the wood
- +No ozone-depleting fumigant involved
- +Can be re-treated if the pallet is repaired with new wood
- +Often preferred for consumer product shipments
- +No fumigant handling during treatment
Methyl Bromide (MB)
Restricted- −Banned or restricted in many countries; check current regulations
- −Ozone-depleting substance under the Montreal Protocol
- −Chemical residues remain on treated wood
- −Often refused by buyers who specify heat-treated pallets
- −Hazardous fumigant that requires careful handling
- −Use is declining under the Montreal Protocol
GMA Pallet Specifications
The GMA pallet — named after the Grocery Manufacturers Association (now the Consumer Brands Association) — is the most widely used pallet in North America. Also called the “standard pallet,” “GMA pallet,” or simply a “48×40,” it is the size most warehouses and trailers are planned around.
The GMA spec describes a 48-inch by 40-inch, stringer-style pallet with notched stringers for partial four-way entry and typical board widths, thicknesses, and nailing patterns. The design suits standard warehouse racking and makes efficient use of trailer space (two pallets fit side-by-side across a standard trailer).
GMA pallets are the most common request we pass to partner suppliers, and they are widely available in recycled and new versions, across grades and with heat-treated options. If you're not sure what size you need, the GMA 48×40 is usually the right starting point.
GMA Pallet Specs
NWPCA Guidelines
The National Wooden Pallet and Container Association (NWPCA) is a major U.S. trade association for the pallet industry. While NWPCA doesn't set enforceable regulations, its guidelines and best practices are widely referenced for pallet manufacturing, repair, and recycling quality.
NWPCA's Pallet Design System (PDS) software is used by many manufacturers to design pallets for specific load requirements, and the association publishes guidance on pallet terminology, repair, and lumber. Grade names like “Grade B” still vary between suppliers, so it pays to confirm definitions.
When you compare quotes, you can ask partner suppliers how they grade and repair pallets and whether they design to NWPCA guidance. Learn more about common grading criteria in our pallet grades guide.
Compliance Requirements by Industry
Different industries have different pallet requirements. Here's what you need to know based on your sector.
Food & Beverage
Food manufacturers often ask for Grade A or new pallets that are clean, dry, and free of contamination, and some ask for heat-treated pallets even for domestic shipments. Check your customer's specifications and current regulations for your products.
HT preferred · Grade A/New
Pharmaceutical
Pharma shippers usually expect a high level of pallet quality and clean, contamination-free packaging. New or Grade A heat-treated pallets are common, and some companies specify plastic pallets. Follow your own quality requirements.
HT common · New/Grade A
International Export
Regulated wood packaging generally must comply with ISPM 15 when crossing international borders, which means treated and marked pallets. The destination country enforces compliance, and consequences can include quarantine, fumigation, or return shipment. Check current regulations for your destination.
ISPM 15 · HT marked
Retail & Distribution
Large retailers often set pallet requirements in their vendor guides, commonly GMA-style 48×40 pallets in Grade A or B condition. Non-compliant pallets can lead to chargebacks or refused shipments, so check your retailer's current guide.
GMA standard · Grade A or B
Automotive
Automotive supply chains often use custom-sized pallets designed for specific parts. Quality requirements vary: engine components may require new pallets with moisture barriers, while bulk fasteners ship fine on Grade B recycled units.
Custom sizes common · Mixed grades
Manufacturing & Warehouse
Internal warehouse operations and domestic B2B shipping have the most flexibility. Grade B and C recycled pallets are a common choice, offering dependable performance at a lower cost. The focus is on structural integrity, not appearance.
Grade B/C · Best value
Get a Free Quote
Need heat-treated pallets or GMA standard pallets? Tell us about your requirements and we will pass your request to partner suppliers; a supplier follows up with a quote.
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From heat-treated export pallets to everyday warehouse pallets, we connect Colorado businesses with partner suppliers who can quote what you need.